She went into the hospital last weekend for treatment of a blood clot in a vein between her brain and skull, behind the right ear. It was discovered during a follow-up examination for the concussion she suffered last month when she fainted and fell while ill with a stomach virus.

If all goes as planned, she'll be able to step down from her post soon. President Obama has nominated Sen. John Kerry, D-Mass., to succeed Clinton. She long ago announced that she would be leaving the administration early in Obama's second term.

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